Apparatus for polishing plate glass



Jan. 8, 1929.

HQ K. HITCHCOCK APPARATUS 'FOR POLISHING PLATE'GLASS Filed oct. 29, 192s4 sheets-sheet 2 Jn. 8, 1929. H. K. HITCHCOCK ,APPARATUS FOR'POLISHINGPLATE GLASS Filed Oc't. 29, 1925 4 Sheets-Sheet Jan. 8, 1929. C

y '1,698,365 H. K. HITCHCOCK APPARATUS FOR POLISHING PLATE GLASS 4sheets-sheet 4 Filed octpze, 1925 Patented Jan. s, 1929.

UNITED. STATES 1 PATlazNTA OFFICE.

HALiann'r` K HITcHooox, or PITTSBURGH, PENNSYLVANIA, AssreNoa To PITTS-runen PLATE- GLASS COMPANY, A CORPORATION or PENNSYLVANIA.

APPARATUS FQR POLISHING PLATE GLASS.

. ipplcatioaled October 29, 1923. Serial No.` 671,374.

The invention relatesto an apparatus for polishing' plate glass. It isparticularly .adapted for use in a straight away operation the lower endof the housing and is secured to in which the glass to besurfaced ispassed continuously beneath a series of grinding and polishing machines,and the invention has its greatest value in this connection, but it isnot limited to use in such connection. It has for its primary objectsthe provision of an improved apparatus, Wherein, (l) a uniform polishingeifect is "secured over the area of glass-passing beneaththe apparatus,vthe polishing mixture is distributed uniformly over the faces of thepolishing felts, the

faces of the felts are automatically cleaned. at

intervals Which can be regulated to suit conditions, (4) the amount ofpolishing mixture to each felt can be independently regulated so as tobe suitable for each character of work being done, (5)- the conduits forthe polishing mixture are kept open and all danger of clogging avoided,and (6) anywaste of the polishing mixture is avoided and all splashingof the polishing mixture eliminated. Certain embodiments of theinvention are illustrated in the accompanying drawings wherein:

Figure 1 is a vertical section through one form of apparatus. Fig. 2'isa plan View of the apparatus of Fig. 1. Fig. 3 is a section on thelinelIIIII of Fig. 1. Fig. 4 is a vertical section through a modifiedform of the apparatus. Fig. 5 is a plan view of the apparatus of Fig. 4.And Fig. 6 is a diagrammatic side elevation View partially in sectionshowing the method of circulating and mix- .ing the rouge and water.

Referring to the construction of Figs. 1, 2 and 3,1 is the spindlehousing `in which is mounted the spindle 2'which projects from therunner frame by means of the key 4. The runner frame'is preferably a,steel casting of the skeleton form indicated in Fig. 2 and carries fiverunner blocks 5, although this number may be variedto suitrequirements,.

it being preferred, however, to use runner blocks of relatively largediameter "as com- -pared with those ordinarily used'so that a lessnumber are used than if smaller runner blocks were employed.

The runner blocks are of annular form, as

i' indicated in Fig. 1 and carry upon their lower sides the annulardiscs 6 of felt `or other yielding material suitable for use with' rougeor other polishing material, such felts being preferably secured to therunner blocks by means of water proof cement. The runner blocks areprovided with hollow shafts 7 which are secured to such blocks by meansof rubber diaphragms 8 clamped at their inner edges to the flanges ofthe shafts by means of the collars 9 held in place by screws or boltsand at their outer edges by means of the collars 10 held in place by thebolts 11. The shafts are journaled in the bearings 12, provided Withsuitable bushings, and disengagement of the Shafts from the bearings,when the runner. frame is raised, is prevented by means of the caps 13which'are screwed down into the endsof the shafts as indicated at 14.The perforations 15 through the centers of the shafts provide conduitsfor the passage of a polishing mixture to the spaces at the centers ofthe blocks, and the diaphragms 8 prevent any splashing or lss of thepolishing mixture. Y .Mounted upon the top of the runner frame is acasting 16 provided with the five annular troughs 17, 18, 19, 20 and 2lwhich communi- "cate with the passages 15 through the runner Thecompartments are supplied intermittent- I ly with the rouge mixture inthe container 27 by means of the wheel 39 mounted for rotation andprovided with the five buckets 40, 41, 42, 43 and 44mounted to swingfreely on the rods 45 extending between the Sides of the wheel, thesebuckets being arranged in-different vertical'planes, so that each onesupplies one of the compartments 34, 35, 36, 37 v1700' and 38. Theswinging movement of the buckets in one direction is stopped by means ofthe stop members 46 on the `periphery of the Wheel, so that upont-herotation of thewheel in the direction indicated by the arrow in Fig. ll, each bucket scoops up a quantity of the polishing mixture, and whenit arrives at the position of the bucket 42 in Fig 1, the contents isdumped into a compartment in the box 33.

` Atop o the tank as indicated at 52.. A 'circu,

polishin The container 27 is supplied with a mixture of rouge and wateror ot 1er polishing material through the' spigot 47, and a. water pipe48 4is also provided -to-give an independent supply of water such pipebeing controlled by means of theiva'lv'e 19a/'The linethod of supyingthe mixture to the pipe 47 is illustrated agrammatically in Fig. 6 inwhich 50 is a mixing tank or laxivator rovided with a circulation 'main51 leading romv the bottom and havin itsOt-her end leading back into thelation of themixture is secured by .means of a pump 53. Properproportions of rouge and water are supplied to the tank and the mixtureis kept agitated j and thoroughly mixed by means of paddles 54 carried bthe shaft 55, such shaft being driven by the shaft, or b any othersuitable means. Leading from t e main `51 are the spigots 47v which goto the .various polishing machines. This method of circulation andmixing insures that the water and rouge will be thoroughly mixed and.that the mixture furnished to all ofthe machines through the spigots 47will b et ve same. The main l is preferably i' made of wood as are alsothes'pigots 47 in order to resist the actionof the rouge composition,which is acid in character, although cor` rosion resistin metal mightVbe used. The

main is prefera ly carried along over the various machines so thatthespigots can discharge directl into the containers 27. There is thuslittle ginger of the mixture clog ing in its Passage from the main tothe container, and i this occurs, the difficulty may quickly be removedby removing the spigot and insertin a -new one. The wheel 39. is drivenfrom t e counter shaft 58 by means of the belt I59 (Fig. 3) the steppulleys 60 and 61 being employed so that the speedof rotation ofthe ithe course of time.

wheel may be regulated to give any desired interval of feed. The amountof feed may be f varied by varying the level of the liquid in thecontainer 27.

g As indicated in Fig. 2, the glass sheet 62 A which is bein polished iscarried upon a table rangement as heretofore described,- a mixture ofrouge and water of the proper character V1s supplled to each runner atseparated inter' vals, in sutlicient quantity so that when a dischargeof the mixture occurs to a runner block,` its surface 1s so softenedthat the rouge forms 'liquid used.

A lt 56 as'singY arounda pulley 57 on the upper en of the By means ofthe feed ar-4 a new face free from the defects before noted,

the old surface being sera edotl' more ori less as the runner passesover t 1e edges of the 'glass sheet depending somewhat on the amount ofranged that this surfacing etl'ect is secured The interval of feed is soar` only when the blocks become ineffective so that the rouge is notscraped oli before it has had anopportunity to do the amount ofpolishing work which it should do. Then it is necessary to give thefelts a more thorough cleaning than is afforded by this regularintermittent discharge of rouge and water, it may be, accomplished 'byincreasing l the Volume of the mixturein the container 27 by addingwater so' that it is very thin, 'or by using only water in the containerfor a short time or feeding water directly to the blocks from a hose. 4t

The discharge 'of the rouge mixture to" the centers of the runners isadvantageous, since there is no waste and the rou e is immediatelyspread between the felt am? the glass. The

annular felt thus acts somewhat as a brush distributing the rougemixture over the surface of the lass so that the face on the felt isquickly re ormed and there is a minimum amount of waste incident to the'mixturetlowing olf yof the side of the table. This feature and thesupplying of the rouge beneath the diaphragmsS promotes economy in theuse of polishing material and assists lnpreventing an accumulation ofrou e over the surface of the runner frame ,and locks and Iprotectingthe bearings and other parts from t e corroding action of the rougemixture. neetion, the hollow shafts 7 are preferably made of some acidresisting composition so that In this conl they will last for a longperiod despite the corrodin action of the rouge mixture.

A furt er substantial advantage is` also in-` l l volved in arrangingthe rouge discharge streams so that their outlets follow the pads inthelr paths of movement in that' the mixture of Vrouge andwater gives acooling effect iplon the glass Where it is of the greatest value. 1

e tendency ofthe annular series of pads or i blocks is to heat the glassin an annular ring which may cause breaka e due to unequal expaiisionafter the glass as passed beneath a number of runners; and the supply ofrouge following along the annular paths tends to com ensate for thiscondition. A

T e method of feed, including the arrangement illustrated in Fig.` 6 isalso of advantage since it ermits all of the machines of a series to efed from the same container or .-tank 50. The -various machines of aseries require a mixture containing a less and less proportion of rougeasthe polishing pro gresses, and this condition may be readi y securedin theapparatus as above described lby supplying a rouge mixture lofthe' same v ,character to all of the containers 27 by means of thespigots '47 and then utilizing the water las pipes 48 to dilute themixture to the proper consistency for the particular polishing stage forwhich thevmachine is bein used.

f If desired, the excess of water to givevthe fnecessary dilution may beapplied to the stream of rouge mixture .anywhere along its travel to thetable, or may be supplied to the table, itself, the result being thesame invall cases. i

Figs. 4 and 5 illustrate a modification, such modification relating tothe runner block construction and the method of supplying the rougemixture from the annular troughs to the blocksthe other `parts of theapparatus being the-same as described'in connection with the apparatusof Figs. 1 to 3, and

being similarly numbered. In this type of construction the runner `block64 is provided with an annular clamp 65 held b the bolts 66, and betweenthis clamp and t e blockis secured a rubber. diaphragm 67 correspond'ing to the diaphragms 8 of Fig-1, but provided with perforations 68, theinner edgef of the diaphragm being clamped to the sleeve 69 by means ofthe bolts 70., The upper end of the'sleeve 69 is threaded to -a cap 71and this cap is secured against the lower side of the runner frame 72 bymeans of the bolt 73 which has a collaror shoulder 74 fitting between.the top of the sleeve 69 and the iiange Y 'on the cap 71. The lowerportion of the bolt 7 3 acts asa spindle or pivot, the v'sleeve 69serving as the bearing therefor. The clamp 65 is provided, with a splashwall75 and the' space inside of this wall is fed with a rouge mixturefrom the ypipe 76 leading "romone of the annular troughs or 'grooves 77such troughs or grooves abeing fed by means of the pipes 78corresponding to the pipes 28 to 32 oi' the Fig. 1 construction. Inthisconstruction as in that of Fig. 1, thediaphra'gm which connects therunner blocky to the spindle is relatively flexible so that` the runnerblock can adjust itself to the surface ofthe glass.` Also in thisconstruction as in that v of Fig. 1, the lower ends of the pipes leadingto the annular troughs are supported by means of abracket 79 clampedaround the` lower endl of the spindle housing.

What I claim is:

l. In combination in polishing apparatus,

a runnerl frame, havingon its upper side a plurality of concentricannular troughs, a plurality of runner blocks carried by the frame,annular" olishin discsof yielding material carried y the b ocks, a'conduit exdown to each o-said troughs for tending supplying apolishingmixture thereto, and conduits leading from the troughs totheopenings at the centers of the discs. y

2. In combination in polishing apparatus,

a runner frame, a plurality o-runner blocks carried thereby, a pluralityof conduits for `conducting a polishing mixture to the runner blocks, acontainer foi-.the polishing mix-` ture, and a rotating device-,in saidcontainer provided with a plurality'of buckets, one for' each conduit,arrangedso that on the Arotation of the devicey each bucket dips up aquantity of the mixture anddischarges it into its conduit.

v3. In combination ingpolishing apparatus, a runner frame having on itsupper si-de a plurality of concentric :annular '.troughs, a plurality ofrunner blocks carried bythe -frame and each provided with. a .facing offrame and each providedwith a facing-ot yielding material, a conduitextending down to each of said troughs for supplying a polishing mixturethereto, means for supplying a polishing mixture to` 'said conduits one`aft-er the other at timed intervalsgfand conduits leading from saidtroughs to a posit-ion 'of discharge adjacent the runner blocks.

5. Inv combination in polishing apparatus, i .e5l .y

a runner frame, a plurality ofy runnerV blocks carried thereby,aplurality'of conduitsV for conduct-ing a polishing mixture to the runnerblocks, a containerufor the polishing mixture, and a rotating device insaid container' provided with av plurality ofbucketsgvone for eachconduit, arranged in series around said rotating devlce So thaton,tl1ejrotat1o n of dip up a yportion offthe mixture and discharge ittooneof said conduits. 1 v i In testimony whereof, I have hereuntosu-bscribed my name this 25th day lof O ct. v1923.

' I HALBERT Kl' HITCHCOCK.

. the device, thebuckets oneV after' the other

